The Grazing Cow

题目描述

[problemUrl]: https://uva.onlinejudge.org/index.php?option=com_onlinejudge&Itemid=8&category=18&page=show_problem&problem=1619 [PDF](https://uva.onlinejudge.org/external/106/p10678.pdf) ![](https://cdn.luogu.com.cn/upload/vjudge_pic/UVA10678/7068656203260693d3e00eb7a4994e24a2f72639.png)

输入输出格式

输入格式


![](https://cdn.luogu.com.cn/upload/vjudge_pic/UVA10678/0ac9775d9c53e3c021a0e8cb86086c24200d0aad.png)

输出格式


![](https://cdn.luogu.com.cn/upload/vjudge_pic/UVA10678/e87658ac36f9bdf2e75e4400a4cf16d558a7b053.png)

输入输出样例

输入样例 #1

3
10 12
23 45
12 18

输出样例 #1

62.517
1366.999
189.670